Tuesday, May 24, 2016

Mid-May El Nino-Southern Oscillation Model Forecasts

The average of the dynamical models should dip below the -0.5°C sea surface temperature anomaly threshold for La Niñaconditions* next month with the average of the statistical models following close behind.
From IRI/Columbia U.:

2016 May Quick Look

Published: May 19, 2016

A monthly summary of the status of El Niño, La Niña, and the Southern Oscillation, or ENSO, based on the NINO3.4 index (120-170W, 5S-5N)Use the navigation menu on the right to navigate to the different forecast sections

During mid-May 2016 the positive tropical Pacific SST anomaly was quickly weakening, now indicating only a weak El Niño. The atmospheric variables continue to support the El Niño pattern, but at much reduced strength. This includes only a mildly weakened Walker circulation and excess rainfall in the central tropical Pacific, failing to extend eastward as it did in previous months.

Most ENSO prediction models indicate a return to neutral by the end of May, with likely development of La Niña (of unknown strength) by fall.

*"Conditions" become a full blown La Niña after three 3-month rolling periods (five months total) below the threshold.